Re: [PATCH v2 5/6] iio: imu: bmi270: Add triggered buffer for Bosch BMI270 IMU

[Justin Weiss <justin@justinweiss.com>]

Jonathan Cameron <jic23@kernel.org> writes:

> On Fri, 18 Oct 2024 16:36:11 -0700
> Justin Weiss <justin@justinweiss.com> wrote:
>
>> Set up a triggered buffer for the accel and angl_vel values.
>> 
>> Signed-off-by: Justin Weiss <justin@justinweiss.com>
> Looks good. One trivial comment inline.
>
> Thanks,
>
> Jonathan
>
>> ---
>>  drivers/iio/imu/bmi270/Kconfig       |  1 +
>>  drivers/iio/imu/bmi270/bmi270.h      |  9 +++++
>>  drivers/iio/imu/bmi270/bmi270_core.c | 56 ++++++++++++++++++++++++++++
>>  3 files changed, 66 insertions(+)
>> 
>> diff --git a/drivers/iio/imu/bmi270/Kconfig b/drivers/iio/imu/bmi270/Kconfig
>> index 0ffd29794fda..6362acc706da 100644
>> --- a/drivers/iio/imu/bmi270/Kconfig
>> +++ b/drivers/iio/imu/bmi270/Kconfig
>> @@ -6,6 +6,7 @@
>>  config BMI270
>>  	tristate
>>  	select IIO_BUFFER
>> +	select IIO_TRIGGERED_BUFFER
>>  
>>  config BMI270_I2C
>>  	tristate "Bosch BMI270 I2C driver"
>> diff --git a/drivers/iio/imu/bmi270/bmi270.h b/drivers/iio/imu/bmi270/bmi270.h
>> index 51e374fd4290..844d70a7d32e 100644
>> --- a/drivers/iio/imu/bmi270/bmi270.h
>> +++ b/drivers/iio/imu/bmi270/bmi270.h
>> @@ -11,6 +11,15 @@ struct bmi270_data {
>>  	struct device *dev;
>>  	struct regmap *regmap;
>>  	const struct bmi270_chip_info *chip_info;
>> +
>> +	/*
>> +	 * Where IIO_DMA_MINALIGN is larger than 8 bytes, align to that
>
> maybe larger than 8 bytes
> on x86_64 I think it is 8 bytes exactly, though I could be remembering that wrong.

Got it. I'll change this to "... IIO_DMA_MINALIGN may be larger than 8
bytes, ..." in v3.

Justin

>> +	 * to ensure a DMA safe buffer.
>> +	 */
>> +	struct {
>> +		__le16 channels[6];
>> +		aligned_s64 timestamp;
>> +	} data __aligned(IIO_DMA_MINALIGN);
>>  };
>>